Update on the pathogenesis of atopic dermatitis.

Atopic dermatitis is a chronic, recurrent, and multifactorial skin-mucosal manifestation resulting from the interaction between elements mainly associated with the skin barrier deficit, the homeostasis of the immune response, neurological aspects, and patterns of reactivity to environmental antigens, which are established in genetically predisposed individuals. In addition to the skin, atopic diathesis involves other organs such as the airways (upper and lower), eyes, digestive tract, and neuropsychiatric aspects, which inflict additional morbidity on the dermatological patient. The different phenotypes of the disease fundamentally depend on the participation of each of these factors, in different life circumstances, such as age groups, occupational exposure patterns, physical activity, pollution, genetic load, and climatic factors. A better understanding of the complexity of its pathogenesis allows not only the understanding of therapeutic targets but also how to identify preponderant elements that mediate disease activity in each circumstance, for selecting the best treatment strategies and mitigation of triggering factors. This narrative review presents an update on the pathogenesis of atopic dermatitis, especially aimed at understanding the clinical manifestations, the main disease phenotypes and the context of available therapeutic strategies.

Efficacy and safety of 0.5% colchicine cream versus 5% 5-fluorouracil cream in the treatment of cutaneous field cancerization: a randomized clinical trial

Abstract Background 5-Fluorouracil (5-FU) is a first-line drug to treat cutaneous field cancerization (CFC). There are few clinical trials with topical colchicine (COL). Objective To evaluate the effectiveness of 0.5% COL cream versus 5% 5-FU cream in the treatment of CFC. Method This was a randomized, open, self-controlled clinical trial. Forty-five patients (90 forearms), with three to ten actinic keratoses (AK) on each forearm, used 0.5% COL cream 2×/day for seven days on one forearm, and 5% 5-FU cream 2× /day, for 21 days, on the other forearm. The dosages were defined based on previous clinical trials for each drug. Adverse effects were evaluated after 14 days and outcomes after 90 days of inclusion. The primary outcome was complete AK clearance and the secondary outcomes were: partial clearance (≥50%), reduction in AK count, assessment of the Forearm Photoaging Scale (FPS), AK Severity Score (AKSS), and adverse effects. Results After 90 days, there was complete clearance of AK in 37% (95% CI 24%-49%) and partial clearance in 85% (95% CI 76%-93%) of the forearms treated with 5-FU,versus 17% (95% CI 7%-27%) and 78% (95% CI 66%-88%) for COL (p > 0.07). There was a percentage reduction of 75% in the AK count of the forearms treated with 5-FU (95% CI 66%-83%) and 64% in those treated with COL (95% CI 55%-72%). Regarding FPS and AKSS, there was improvement in both groups, with no difference regarding FPS (p = 0.654), and 5-FU superiority for AKSS (p = 0.012). Study limitations Single-center study. Conclusions 5-FU and COL are effective for treating CFC, with neither showing superiority regarding the reduction in AK counts.

Prevalence and factors associated with olfactory impairment among patients with acne treated with oral isotretinoin: a cross-sectional study.

OBJECTIVE: This study aimed to investigate the prevalence and factors associated with olfactory dysfunction in individuals exposed to Isotretinoin (ISO) for the treatment of acne, using the University of Pennsylvania Smell Identification Test (UPSIT®). METHODS: This cross-sectional study enrolled age and sex-matched patients with acne who were current users of oral ISO and unexposed controls without olfactory complaints. UPSIT® and a validated questionnaire (Nasal Obstruction Symptom Evaluation) were administered to evaluate nasal obstruction in patients exposed to ISO. RESULTS: A total of seventy patients were recruited, with 35 in the exposed group and 35 in the unexposed group, consisting of 18 males and 17 females in each group, aged from 17 to 47 years. The prevalence of olfactory dysfunction was higher in the exposed group compared to the non-exposed group (62.9% vs. 17.1%), yielding a Prevalence Ratio (PR) of 3.7 (95% CI 1.9-7.1). However, no participants were categorized as anosmia or severe hyposmia and the majority of dysfunction was mild hyposmia compared to moderate hyposmia (51.5% vs. 11.4%). Among the exposed individuals, gasoline, orange, coffee, and wood exhibited the highest rates of identification errors (≥54%). Olfactory function demonstrated a negative correlation with treatment duration (p = 0.01), cumulative dose (p = 0.02), and nasal obstruction (p = 0.02). CONCLUSIONS: Olfactory dysfunction was more prevalent among ISO users, despite the patients being unaware of the disorder. Olfactory changes were correlated with treatment duration, cumulative dose, and nasal obstruction. LEVEL OF EVIDENCE: Level 4.

Zoonotic Sporotrichosis outbreak: Emerging public health threat in the Amazon State, Brazil.

BACKGROUND: Sporotrichosis is the most common subcutaneous mycosis caused by Sporothrix spp. Traditionally, it is transmitted through injuries involving plant debris. However, over the past few decades, there has been an epidemic increase in human cases resulting from contact with infected animals, particularly cats, in various regions of Brazil. In this report, we report a notable increase in both human and animal cases within the Brazilian Amazon state. METHODOLOGY/PRINCIPAL FINDINGS: An ecological study was conducted by analyzing official records of human and animal sporotrichosis diagnosed in the state of Amazon from 2020 to 2023. Data including patient demographics, clinical manifestations, mycological examination results, and species identification through PCR confirmation were evaluated. During this period, a total of 950 human cases and 2,823 animal cases of sporotrichosis were reported at an exponential rate, since no human cases were registered in 2020. The spatial and temporal dispersion of human sporotrichosis followed that of animal cases, moving from downtown areas to the periphery. Contact with infected animals was reported in 77.7% of cases, with cats being the most commonly implicated (73.5%). Only 66.7% of individuals underwent mycological examination. Among the positive cultures for Sporothrix spp., 65.4% were identified as S. brasiliensis. All patients were treated with systemic antifungals. CONCLUSIONS/SIGNIFICANCE: This study highlights a rising incidence of sporotrichosis among animals and humans in the Brazilian Amazon region over the past four years, with S. brasiliensis being the predominant agent. Collaborative efforts involving healthcare professionals, veterinarians, and public health authorities are crucial to implement effective control measures, educate populations at risk, and promote responsible guidance for pet guardians. These measures are essential to mitigate the burden of epidemic sporotrichosis in Brazil.

Complications of collagen biostimulators in Brazil: Description of products, treatments, and evolution of 55 cases.

BACKGROUND: Complications of temporary and permanent fillers have been extensively studied. However, there is a lack of comparative data regarding poly-L-lactic acid (PLLA), calcium hydroxyapatite (CaHA), and polycaprolactone (PCL) known as collagen biostimulators. AIMS: This study addressed the complications of collagen biostimulators concerning their diagnosis, type of product, treatment, and monitoring. PATIENTS/METHODS: An electronic questionnaire was sent to Brazilian dermatologic ultrasound experts to identify complications related to biostimulators. The type of biostimulator, location of application, number of vials injected, application plan, time between injection treatment and complication, injector profile, treatment, and prognosis were assessed. RESULTS: Fifty-five cases were identified, of which 49.1% were caused by PLLA-Elleva®, 23.6% by CaHA (alone or combined with hyaluronic acid), 20.0% by PLLA-Sculptra®, and 7.3% by PCL. The most affected area was the face (72.7%), with nodules being the most common clinical form (89.1%), generally occurring late (60.0%) (>1 month). Only one case was injected at an incorrect depth (musculoaponeurotic system-SMAS). Despite several treatments, including saline (45.5%), hyaluronidase (25.5%), diluted corticosteroids (23.6%), and energy-based devices (10.9%), only five cases showed complete resolution. Hyaluronidase was beneficial in complications related to fillers when there was an association of calcium hydroxyapatite with hyaluronic acid (p < 0.01). CONCLUSIONS: Complications from collagen biostimulators were more common on the face, typically manifesting about 1 month after treatment. These issues seemed to be related more to the properties of the products rather than inadequate technique. Furthermore, hyaluronidase demonstrated efficacy only in cases where there was an association with HA.

Efficacy and safety of 0.5% colchicine cream versus 5% 5-fluorouracil cream in the treatment of cutaneous field cancerization: a randomized clinical trial.

BACKGROUND: 5-Fluorouracil (5-FU) is a first-line drug to treat cutaneous field cancerization (CFC). There are few clinical trials with topical colchicine (COL). OBJECTIVE: To evaluate the effectiveness of 0.5% COL cream versus 5% 5-FU cream in the treatment of CFC. METHOD: This was a randomized, open, self-controlled clinical trial. Forty-five patients (90 forearms), with three to ten actinic keratoses (AK) on each forearm, used 0.5% COL cream 2×/day for seven days on one forearm, and 5% 5-FU cream 2× /day, for 21 days, on the other forearm. The dosages were defined based on previous clinical trials for each drug. Adverse effects were evaluated after 14 days and outcomes after 90 days of inclusion. The primary outcome was complete AK clearance and the secondary outcomes were: partial clearance (≥50%), reduction in AK count, assessment of the Forearm Photoaging Scale (FPS), AK Severity Score (AKSS), and adverse effects. RESULTS: After 90 days, there was complete clearance of AK in 37% (95% CI 24%-49%) and partial clearance in 85% (95% CI 76%-93%) of the forearms treated with 5-FU,versus 17% (95% CI 7%-27%) and 78% (95% CI 66%-88%) for COL (p > 0.07). There was a percentage reduction of 75% in the AK count of the forearms treated with 5-FU (95% CI 66%-83%) and 64% in those treated with COL (95% CI 55%-72%). Regarding FPS and AKSS, there was improvement in both groups, with no difference regarding FPS (p = 0.654), and 5-FU superiority for AKSS (p = 0.012). STUDY LIMITATIONS: Single-center study. CONCLUSIONS: 5-FU and COL are effective for treating CFC, with neither showing superiority regarding the reduction in AK counts.

Oral Minoxidil vs Topical Minoxidil for Male Androgenetic Alopecia: A Randomized Clinical Trial.

Importance: There has been increased interest in low-dose oral minoxidil for androgenetic alopecia (AGA) treatment. However, the efficacy of oral minoxidil for male AGA is yet to be evaluated in comparative therapeutic trials. Objective: To compare the efficacy, safety, and tolerability of daily oral minoxidil, 5 mg, vs twice-daily topical minoxidil, 5%, for 24 weeks in the treatment of male AGA. Design, Setting, and Participants: This double-blind, placebo-controlled randomized clinical trial was conducted at a single specialized clinic in Brazil. Eligible men with AGA aged 18 to 55 years classified using the Norwood-Hamilton scale as 3V, 4V, or 5V were included and randomized. Data were collected from January to December 2021, and data were analyzed from September 2022 to February 2023. Interventions: Participants were randomized 1:1 into 2 groups: oral minoxidil, 5 mg, daily and topical placebo solution; or 1 mL of topical minoxidil, 5%, twice daily and oral placebo for 24 weeks. Main Outcomes and Measures: The primary outcome was change in terminal hair density on the frontal and vertex regions of the scalp. The secondary outcomes were change in total hair density and photographic evaluation. Results: Among 90 enrolled participants, 68 completed the study; of these, the mean (SD) age was 36.6 (7.8) years. A total of 33 participants were enrolled in the oral minoxidil group and 35 in the topical treatment group. Both groups were homogenous in terms of demographic data and AGA severity. For the frontal area, the mean change from baseline to week 24 between groups was 3.1 hairs per cm2 (95% CI, -18.2 to 21.5; P = .27) for terminal hair density and 2.6 hairs per cm2 (95% CI, -10.3 to 15.8; P = .32) for total hair density. For the vertex area, the mean change from baseline to week 24 was 23.4 hairs per cm2 (95% CI, -0.3 to 43.0; P = .09) for terminal density and 5.5 hairs per cm2 (95% CI, -12.5 to 23.5; P = .32) for total hair density. According to the photographic analysis, oral minoxidil was superior to topical minoxidil on the vertex (24%; 95% CI, 0 to 48; P = .04) but not on the frontal scalp (12%; 95% CI, -12 to 36; P = .24). The most common adverse effects in the oral minoxidil group were hypertrichosis (22 of 45 [49%]) and headache (6 of 45 [14%]). Conclusions and Relevance: In this study, oral minoxidil, 5 mg, once per day for 24 weeks did not demonstrate superiority over topical minoxidil, 5%, twice per day in men with AGA. Trial Registration: Brazilian Registry of Clinical Trials Identifier: RBR-252w9r.

Prurigo: review of its pathogenesis, diagnosis, and treatment.

Prurigo is a reactive, hyperplastic skin condition characterized by pruritic papules, plaques, and/or nodules. The temporal classification includes acute/subacute and chronic disease (≥ 6 weeks), with different clinical variants, synonymies, and underlying etiological factors. The immunology of chronic prurigo shows similarities with atopic dermatitis due to the involvement of IL-4 and IL-13, IL-22, and IL-31. Treatment includes antihistamines, topical steroids, dupilumab, and JAK inhibitors. Several conditions manifest clinically as prurigo-like lesions, and the correct clinical diagnosis must precede correct treatment. Furthermore, chronic prurigos represent a recalcitrant and distressing dermatosis, and at least 50% of these patients have atopic diathesis, the treatment of which may induce adverse effects, especially in the elderly. The quality of life is significantly compromised, and topical treatments are often unable to control symptoms and skin lesions. Systemic immunosuppressants, immunobiologicals, and JAK inhibitors, despite the cost and potential adverse effects, may be necessary to achieve clinical improvement and quality of life. This manuscript reviews the main types of prurigo, associated diseases, their immunological bases, diagnosis, and treatment.